Mark internal nss symbols with attribute_hidden to allow direct access
within libc.so and libc.a without using GOT nor PLT.

Tested on x86-64 with and without --disable-nscd.

	[BZ #18822]
	* grp/initgroups.c (__nss_group_database): Removed.
	(__nss_initgroups_database): Likewise.
	* nscd/gai.c (__nss_hosts_database): Likewise.
	* nss/XXX-lookup.c (DATABASE_NAME_SYMBOL): Likewise.
	* posix/tst-rfc3484-2.c (__nss_hosts_database): Likewise.
	* posix/tst-rfc3484-3.c (__nss_hosts_database): Likewise.
	* posix/tst-rfc3484.c (__nss_hosts_database): Likewise.
	* sysdeps/posix/getaddrinfo.c (__nss_hosts_database): Likewise.
	* nss/getXXent.c (INTERNAL (REENTRANT_GETNAME)): Add
	attribute_hidden.
	* nss/nsswitch.c (__nss_database_custom): Define only if
	USE_NSCD is defined.
	(__nss_configure_lookup): Use __nss_database_custom only if
	USE_NSCD is defined.
	* nss/nsswitch.h (__nss_database_custom): Declare only if
	USE_NSCD is defined.  Add attribute_hidden.
	(__nss_setent): Add attribute_hidden.
	(__nss_endent): Likewise.
	(__nss_getent_r): Likewise.
	(__nss_getent): Likewise.
	(DEFINE_DATABASE): Declare __nss_##arg##_database.

qsort_r is defined in the same file as qsort, but is not an ISO C
function, so should be a weak alias for __qsort_r.  The uses in
getaddrinfo should also call __qsort_r, since getaddrinfo is a POSIX
function and qsort_r isn't.  This patch implements this.  Because nscd
uses the getaddrinfo sources outside libc, as do the tst-rfc3484
tests, a #define of __qsort_r to qsort_r is added there alongside the
similar defines for other libc-internal symbols used in getaddrinfo.

Tested for x86_64 (testsuite, and that disassembly of installed shared
libraries is unchanged by the patch).

	[BZ #17571]
	* stdlib/msort.c (qsort_r): Rename to __qsort_r and define as weak
	alias of __qsort_r.
	(qsort): Call __qsort_r instead of qsort_r.
	* include/stdlib.h (qsort_r): Do not call libc_hidden_proto.
	(__qsort_r): Declare.  Call libc_hidden_proto.
	* sysdeps/posix/getaddrinfo.c (getaddrinfo): Call __qsort_r
	instead of qsort_r.
	* nscd/gai.c (__qsort_r): Define to qsort_r.
	* posix/tst-rfc3484.c (__qsort_r): Likewise.
	* posix/tst-rfc3484-2.c (__qsort_r): Likewise.
	* posix/tst-rfc3484-3.c (__qsort_r): Likewise.

        * sysdeps/posix/getaddrinfo.c (default_scopes): Map RFC 1918
        * addresses
        to global scope.
        * posix/tst-rfc3484.c: Verify 10/8, 172.16/12 and 196.128/16
        addresses are in the same scope as 192.0.2/24.
        * posix/gai.conf: Document new scope table defaults.

The posix/tst-rfc3484* test cases caused warnings in newer gccs
because the unused but copied sin_zero part of sockaddr_in wasn't
explicitly initialized.

	opr.ctx_type.
	(calc_first): Initialize constraint field.
	(duplicate_node_closure): Use it instead of special casing ANCHORS.
	Use search_duplicated_node to avoid loops.  Fix grammar.
	(duplicate_node): Merge constraint field for all node types.
	(calc_eclosure_iter): Look at constraint field for all node types.
	* posix/regex_internal.c (create_cd_newstate): Don't look at
	create_cd_newstate.

	* posix/tst-rfc3484.c: Add dummy definition of _res_hconf_init.
	* posix/tst-rfc3484-2.c: Likewise.
	* posix/tst-rfc3484-3.c: Likewise.

	field.  Use sockaddr_in6 for source_addr.
	(get_scope): Change type of parameter to sockaddr_in6.  Adjust.
	(match_prefix): Likewise.
	(get_label): Likewise.
	(get_precedence): Likewise.
	(rfc3484_sort): Change to use indirect access to results array.
	Adjust to use of sockaddr_in6.  Replace service_order test with
	simple index comparison.
	(getaddrinfo): Define order array.  Initialize it.  Don't initialize
	service_order field.  Adjust qsort_t calls.  Access sorted result
	array indirectly through order array.
	* posix/tst-rfc3484.c: Adjust for change of rfc3484_sort.
	* posix/tst-rfc3484-2.c: Likewise.
	* posix/tst-rfc3484-3.c: Likewise.

	(get_scope): For IPv4 scope, use scopes table.
	(fini): Free scopes table if necessary.
	(free_scopelist): New function.
	(scopecmp): New function.
	(gaiconf_init): Also handle scopev4 entries.
	* posix/tst-rfc3484.c (do_test): Initialize scopes.
	* posix/tst-rfc3484-2.c (do_test): Likewise.
	* posix/gai.conf: Document scopev4 defaults.
	* posix/Makefile (tests): Add tst-rfc3484-3.
	* posix/tst-rfc3484-3.c: New file.